I just was looking for a clarification, because it seems a bit hit or miss on this. I had a new FS/T thread of mine closed due to an old link in my profile to my old FS/T thread from 2013, which led to a warning, but it also said that the forum only allows for USD to be used here, and that BTC is not a valid form of payment. I've never actually seen that in the rules, i've seen prices for Euro's & CAD when the traders have been based in those areas in the past; and I've seen threads where BTC is listed as a payment type that are both allowed (and i've also seen some where it's been not allowed), but I do not see anything specifically in the rules that disallow such payment sources or currencies from being used.